smarty截取字符串truncate函数介绍

//index.php
$smarty = new Smarty;
$smarty->assign('articleTitle', 'Two Sisters Reunite after Eighteen Years at Checkout Counter.');
$smarty->display('index.tpl');
//index.tpl
{$articleTitle}
{$articleTitle|truncate}
{$articleTitle|truncate:30}
{$articleTitle|truncate:30:""}
{$articleTitle|truncate:30:"---"}
{$articleTitle|truncate:30:"":true}
{$articleTitle|truncate:30:"...":true}

输出结果：

Two Sisters Reunite after Eighteen Years at Checkout Counter.
Two Sisters Reunite after Eighteen Years at Checkout Counter.
Two Sisters Reunite after…
Two Sisters Reunite after
Two Sisters Reunite after—
Two Sisters Reunite after Eigh
Two Sisters Reunite after E…

<?php
function smarty_modifier_truncate_utf($string, $length = 80, $etc = '...')
{
 $result = '';
 $string = html_entity_decode(trim(strip_tags($string)), ENT_QUOTES, 'utf-8');
 for($i = 0, $j = 0; $i < strlen($string); $i++)
 {
  if($j >= $length)
  {
   for($x = 0, $y = 0; $x < strlen($etc); $x++)
   {
    if($number = strpos(str_pad(decbin(ord(substr($string, $i, 1))), 8, '0', STR_PAD_LEFT), '0'))
    {
     $x += $number - 1;
     $y++;
    }
    else
    {
     $y += 0.5;
    }
   }
   $length -= $y;
   break;
  }
  if($number = strpos(str_pad(decbin(ord(substr($string, $i, 1))), 8, '0', STR_PAD_LEFT), '0'))
  {
   $i += $number - 1;
   $j++;
  }
  else
  {
   $j += 0.5;
  }
 }
 for($i = 0; (($i < strlen($string)) && ($length > 0)); $i++)
 {
  if($number = strpos(str_pad(decbin(ord(substr($string, $i, 1))), 8, '0', STR_PAD_LEFT), '0'))
  {
   if($length < 1.0)
   {
    break;
   }
   $result .= substr($string, $i, $number);
   $length -= 1.0;
   $i += $number - 1;
  }
  else
  {
   $result .= substr($string, $i, 1);
   $length -= 0.5;
  }
 }
 $result = htmlentities($result, ENT_QUOTES, 'utf-8');
 if($i < strlen($string))
 {
  $result .= $etc;
 }
 return $result;
}
?>